Hinged last.



Patented Oct. 5, 1909.

, 30. itself, and by providing a forepart and heelfr onmcn.

.EDWIN O. KRENTLER, OF DETEG-IT, MICHIGAN, AiSSIGNOR TO KRENTLER-ARNOLDHINGE LAST COMPANY, OF DETROIT, MICHIGAN, A CORPORATIGN 0F MICHIGAN..

HINGED LAST.

936,138. Specification of Letters Patent. atented @en 5, 1909.

Application led May 3, 1909. Serial No. 493,503.

To all whom it 'may concern:

Be it known that l, EDWIN O. KPENTLER, a citizen of the Unite-d States,and resident v of Detroit, in the county of Wayne and '.3 State ofMichigan, have invented an lmprovement in Hinged Lasts, of which thefollowing description, in connection with the accompanying drawings, isa specification, like numerals on the drawings representing like' parts.

To keep pace with the modern machinery and processes used in-shoemanufacture, it Y becomes constantly necessary to provide still ystronger hinged lasts, as the early forms of hinged lasts, althoughsufficiently strong and practical for shoe manufacture as thenconducted, fail'to stand up to the present requirementsl Accordingly mypresentinvention aims to provide a hinged last capable of enduring theutmost degree of vertical and twisting strains, blows, and rough usageto which a last is subjected, at the present time. Ithave secured thisdesired object by -providing an interlocking construction of such-shape'at the hinge joint that the vertical and twisting strains (as forinstance those brought on the last during the leveling process) aresustained almost entirely by the contacting surfaces or walls of thewood part as nearly as possible with uncut, intact or integral abuttingends. y

As `heretofore constructed, ithas been considered necessary in hingedlasts to provide saw cuts and kerfs in the'abutting ends Aof thelast-parts at the hinge joint for receiving .the hinging means, lockingmeans, etc., and I have found that most of the weaknessesl and breakagesand defects of lthe 40 hinged last in use have been due to thiscuttingawvay of the wood and the consequent introduction'of lines andplanes of weakness which promote the' splitting and breaking down of thelasts.l I, eliminate all thesesimply by providing a relatively small andhigh knuckle joint of considerable overlapping eXtent, and connect v thelast-parts by a .central cylindrical dowel-like hinge which necessitatesmerely theyboring of a short longitudinal hole intojthe end oftheforepart and intothe end of the heel-part the hole in the latterbeing`enlargedslightlyV ,to permit the required pivotalv movement of;the-heel-part. 4 By this means. the? co'ncavlorl'f joint take up alltwisting strains and give mutual support against vertical, longitudinaland all other strains, while the single dowellikehinge in the said twobored holes inentioned is surrounded on all sides by the virgin wood,which, being irrtact or uncut, affords the greatest strength possibleagainst splitting and the like. As neither last-part contains anyangular recess, kerf,or cnt` transversely through or across its secantend, there is present no tendency to split or to start a cleavage in anyparticular direction. Furthermore, as my last depends for its mainstrength upon the intact wood and the hrm interlocking relation of thecurved surfaces of the wood at the knuckle joint. l provide speciallocking means for maintaining the contacting surfaces of the wood alwaysin unyielding, mutual-supporting engagement when the last is inlengthencd Iposition.

The further constructional details of my invention and advantagesthereof will be pointed out more at length in the course of thefollowing description, considered with reference to the accompanyingdrawings, in which I have shown a preferred embodiment of the invention.

In the drawings, Figure l represents in side elevation, partly brokenaway, a last constructed according to my invention: Fig. ,2 is a viewthereof inside elevation showing the last collapsed: Fig. 3 is across-sectional View thereof at the joint taken on.the line 3 3, Fig. l,looking toward the forepart: and Fig. 4t is a cross-sectional viewlooking toward the heel-part taken on the line l, Fig. l. n

For convenience of i illustration, `l have shown a conventional form oflast, comprising a forepart l and a heel-part '2. Instead of severingthese parts from each other along the usual lines which have betr; dlong followed in hinged lasts, l provide. a knuckle 3 of short radiusinthe heel-'part having 'its surface a curved c'oncentrically from thepivotcenten 5 and carried at'its 55, convex surfaces ofthevshort-,radievis"knuckle rpart, overlapping practically the entireknuckle of the heel-part and preferably extending rearwardly to thepivot thereof, By

- this means notfonly is the convex surface of the knuckle 4held firmlyand solidly in the concave complemental .seat 9 forniedY therefor in theforepart, but the projecting end 8, extending as it does throughout theentire width of the last and rearwardly sufliciently to provide a broadhorizontal bearing or support, 'insures a bracing strength y orstrut-like eect which adds very materially'to the total strength of thelast-joint.

The end of the projection 8 abuts squarely againstthe adjacent end. orwall of the heelpart, and gives an exceedingly strong bracing effect tothat which has already been mentioned. Also this constructionresists alltendency of the last to buckle or collapse bottomward. At its top sidevthe last-parts are severed along the lines-10, ll'respectively so` asto provide a lgap or opening 12 to permit one part to turn on thev otherabout the pivot 5. A single hole is bored at 13 into the forepart and at14 into the heelpart corresponding 4in size to the hinge ortubular plug15 (laterally enlarged verticallyl in theheel part topermit the pivotalaction) which is then driven thereinto and4 secured by pins or rivets 5,16, the former constituting the pivot or hinge pintle of the last aboutwhich the heel-part turns in moving from shortened to Alengthenedposition or vice versa. In a last of this description, in l which the'wood is depended upon for givingthe main strength, etc., more or lessshrinkage will inevitably take place, and accordingly I screw ,into theheel-part a small threaded stud 17 whose forward end terminates" closeto the forepart when the last 'is in extended or lengthened position,and *piv ".oted at 18 on the adjacent wall of the fore- 'strength part awear-plate orlatch 19 which is normally held under tendency to. moveacross the front end of the pin 17 by a spring 20. Thus when the last isturned into its fully lengthened position,l the plate 19 snaps tightlyin front of the pin 17 for the latter lto bear against. As thelastshrinks or the plate wears, the pin 17 is turned correspond-- inglyoutward so asto maintain at all times -a perfectly snug tight fit. Theplate 19 is provided with an rear or finger-hold 21 to 2permit it to beconveniently moved back# lward by the operator, andthe heel-part ispreferably cut away at 22therefor.

I am aware thatlasts `have been heretofore constructed or proposed witha knuckle joint (as shown lfor instance in my Patent No. 864,654 or thePym patent No. 608,006), but

never as herein shown nor withthe advantages herein set forth, but I donot claimthe` 'same broadly herein, but only when s o con-y structed asto secure the' advantages of andoperation already .fexplalned jrangement of union or hinging member is also new and herein claimed inits coperative relation to the adjacent parts and construction" AlsoIwish it understood that Ycations in constructional details andcombideparting from Ithe spirit and scope of the inventionaslhereinafter claimed.

l Having described my invention, what I claim as new and desireto secureby Letters Patentis:. t l

. 1. A hinged last, comprising fore-part in the socket-containing partto hold said plug immovably in the last, and a pivot pin extendingthrough the opposite end of said plug and into the adjacentlast-partconcenknuckle having vertical enlargement, suiicient only topermit the requisite pivotal movement of the heel part, the wood of-said last-parts around said holes being otherwise uncut andintact. y

'2. A hinged last, having a heel part provided with a knuckle ofrelatively short radius projecting from .its front end and extendinghorizontally across the last, a forepart provided with a complementalconcave socket in contact with which'said knuckle'is lower endprojecting rearwardly to overlap the knuckle and abut against the `heelpart for resisting vertical and longitudinal vpreslsures, said fore-partand heel part having central longitudinal hinge-holes formed in theirabutting socket and knuckle ends, the -wood of said last-parts'aroundsaid holes being circumferentially intact about the'hingeholes. at .thesecant ends of the last-parts, a

pin extending through' the fore-part and for- -'ward end of said plugfor retaining'the lat-A ter immovably in the'forepart, and a transversepivot pin .extending through said knuckle and-the rear end lof'said plugon which the heel part swings with relation to the forepart.' f -I 3. Ahingedlast having a heel-part pror'einafter claimed. The 'specialardiu's projecting from its front end and -exatending horizontallyacross the last land my invention is capable of various modifi.

-nation and arrangement ofl partsv withoutv trically of said knuckle,said hole in thel arranged to turn, said forelpart having its rigidvplug held inl said holes, a transverse I videdwith a knuckle ofrelatively short ra--F and a heel part, one part being provided; 83

means cooperating with the .walls of the hole seance teriniiiating onits under side Within the *i turn, said torepart having its lower endprojecting,rearivardlyto overlap the entire kinickle and abut againstsaid wall from said knuckle to the bottoni' of thelast for resistingvertical. and longitudinal pressures, antlvf'igigid hinging meansembedded Within #aid knuckle and pivoted concentrically therein andinunovably securedin the .torep'art.

Il. Ei hii'iged last lia-ving a heel-part provided ivit h a knuckle ofrelatively short. ra dius projecting troni its front end and extendinghorizontally across 'the last and terminating ou its underside Withinthe body of the last above the bottoni, and having a 'wall extending`thence dovvntvardl;v to the bottoni orn the last in position to resistlongitudinal strains, a orepart provided 'with a conipleinental concavesocket in contact with which said knuckle is arranged to turn, saidorepart having its lower end projectingv rearvvardl to overlap theentire knuckle and abut against said Wall from said knuckle to thebottoni of the last for resisting vertical and longitudinal pressures'7said forepart and heel-part having central longitudinal hingeholesi'roruied in their abutting socket and knuckle ends, the Wood of saidlast-parts around said holes being circuniferentially intact about thehinge-holes at the secant ends ofthe last-parts,` a, rigid plug held insaid holes, a transverse pin extending ihrough'the forepart. and forwardend of said plug for retaining the latter innnovable in the torepart,and a transverse pivot pin extending through said knuckle and the rea-r'end of said plug on which the heel-part swings o.

`with relation to the forepart. hinged last, having a heel part provided'with a knuckle of relatively short radius projecting from its front endand eX- tending horizontally across the last, a forepart provided with acoinplcniental concave socket in contact with which said knuckle isarranged to turn, said iorepart having its vlovver end projectingrearwardly to overlap the knuckle and abut against the heel part forresisting vertical 'and longitudinal presseres7 said forepart, and heelpart having central longitudinal,hingsholes formed intheir abuttingsocket and knuckle ends, shape-d to receive a. plug connection andperuit 'the necessary last. inoveinents, and the surrounding woodthereof being othertvlse uncut and in original 'intact osrtion, and aplug-like connection fitted an( secured at its opposite ends in saidhlngehoies in the iorenart and heel para; r aspectively to per-rait theknuckle to turn in the socket While nreventing vthe separation of thelast-:garten (S. A 'hinged last, comprising, a t'orepart and heel-part,one of which is provided with a projecting knuckle extendingtransversely across the last and terminating on; under side at aninterior point-in the .bodyj f last above the bottonn" afifid the 5@thewhich is provided with a' conipleinental cave socket in which said toturn, the last-part (Ing: having its adjacent .bottom7l d overlap 'thesocket to the'eittrcne o ver2-end thereof at said interior 1point i; thAhi'dy idf the last above the bottoni, vsaid- ,tyfe lastvparts lirontsaid interior pointto thefbottom 'of the last 'having uprightabuttingWalls for resisting longitudinal and vertical pres surcs brought uponthe last, said two lastparts at approximately the transverse andvertical middle of their knuckle and socket respectively having alongitudinal hole,

shaped to receive a plug connection and per mit the necessary lastmovements7 and the surrounding Wood thereof being otherwise uncut and inits original intact position, and

a plug-like connection fitted and secured at its opposite ends in saidhole in the torepart and heel-part respectively to permit the knuckle toturn in the socket While preventing'the separat-ion of the last-parts.

' 7. A hinged last, comprising a orepart and heel-part, one of which isprovided` With a projecting knuckle extending transversely across thelast and terminating on its under side at an interior point in the bodyof the .last above the bottoni, and the other of which is provided Iwitha coinpleinental concave socket in which said knuckle is seated to turn,the last-part vcontaining' said sockethaving its adjacent bottoni endarranged to overlap the socket. to the extreme loWer'endV thereof atsaid interior point in the body of the last above the bottoni, said twolast-parts from said interior point to the bott-oni of the last lia-vingupright abutting walls for resisting' longitudinal and vertical.pressures brought upon the last, said two last-parts at approximatelythe transverse and vertical middle of their knuckle and socketrespectively having a longitudinal hole the hole in the knuckle havingvertical elongation to permit of the pivotal action of the heel part.,

andl the surrounding Wood thereof beingV otherwise uncut andin itsoriginal int-act positiona plugdike connection fitted and secured .n itsopposite ends in said hole in the orepart and heel-part respectively toperinit the knuckle to turn in the socket While terininatiifig close tothe tace of the opposite e denounced last-part, and a Wear-plate movableinto and out of position across the end of said pin.,

8. In a, hinged last, a forepart and heelw part pivotally connected andseparated so as f the opposite last-part.

to provide cent upper ends,

an opening between their adja7 combined with a pin ad- .j ustablymounted to project across said opento provide an. opening between theiradja- 1 15 cent upper ends, combined with a pin threaded into'the faceof one last-spartto project across said opening close tothe adjacentface of the opposite last-part, ai Wear-plate pivotally mounted on theface of the latter last-partto swing across the end of said pin when thelast-parts are in fully lengthened position, and a spring for normallyholding said plate under normal tendency to move into the last-mentionedposition.

vIn testimony whereof, I have signed my name to this specification, inthe presence of two' subscribing Witnesses.

EDWIN o.` KRENTLER.

Witnesses lV. A. FRASER, '0. E. FREEMAN.

